CIVILIZING INFLUENCES. 195 
bon; the bobolink has kept pace with the widening eulti- 
vation of rice and grain fields; the red-headed woodpecker 
has retreated from New England; the Arkansas flycatcher 
has multiplied and spread as a town bird through all the 
cities and villages from Council Bluffs to Denver; the ra- 
ven has gradually retired before the wood-cutter, until it has 
almost ceased to exist; while year by year the crow has ex- 
tended its range, without seeming in the least to diminish 
its force in the older districts, but crowding the wild and 
refractory raven farther and farther beyond the frontier. 
Although none have abandoned their old way of life so 
completely as the swallows, many other birds have _profit- 
ed by the constructions and friendship of the human race. 
The bluebird and house-wren, chickadees and nuthatches 
dig holes in the fence-posts conveniently rotting for their 
use; and even such wild species as the western flycatcher, 
great-crested kingbird, and Bewick’s wren, occasionally at- 
tach themselves to mankind, and hatch their young under 
his roof for greater security. Even the whippoorwill and 
nighthawk, asleep all day in the swamp, are glad to come 
to the farmer’s house in the evening, and now and then to 
deposit their eggs on a flat roof. In the Rocky Moun- 
tains I have seen flocks of white ptarmigans nimbly hop- 
ping around the door-steps of miners who were seeking 
